Activity Remote plugin not working on any site..!?

Hi Davide,
Remote plugin stoped working last Oct.2, 2012.. I have 15 open projects where I'm working over randomly for extension maintenace (that's a mix of Joomla! 1.5.26 & 2.5.7 sites)
There is not a good reason that make them to have the tracktime remote plugin stopped reporting activities task...
-Those sites have been moved from one VPS to other VPS/ IP, inside the same Data Center and they have been updated to the latest version of Akeeba AdmintoolsPro 2.4.0... Outside of this recent changes all the sites remain as they were at the older VPS/IP.
- I have AdminTools 2.4.0 installed on my 'tracktime' site, too
- I have verified that linked user inside the plugin, inside every customer site, is correctly set as like its corresponding assigned 'project' and 'hour stack' and all of them match with its corresponding projects and hours stack defined on my 'tracktime' site.
- All involved VPS servers have cURL enabled at PHP
Perhaps, the AdminToolsPro WAF or its 'restrictive' HtaccessMaker .htaccess file are blocking the plugin feature?... Any light you may bring to solve those problems will be very welcome.
Thanks in advance for attention & quick feedback,
Rgrds,
GammX1

Thanks Davide!

I'll try to install AdminTools pro and see if it's stopping anything (maybe I'll try to get in touch with Nicholas, too).
>> You will not get Nicholas available till next Oct. 23 +/- (He is attending a Joomla! Conference right now)

Before the move, everything was working?
>> No all of them as reported before on other post:
-The Old VPS was build with PhP under 'Apache_module' and the reason to move to the new one to CGI/FastCGI under fcgid_module to obtain the same user under joomla! and under the site owner (allowing to keep restricted CHMOD permissions with no one over 755 for directories and 644 for files). On the older VPS some sites worked correctly but those sites are not working now running inside the new VPS. The other change is the AdminTools 2.4.0 upgrade. I don't see any reason why the mentioned configuration could stop the plugin to work...!?... Perhaps, this info. may help you!

Maybe we'll consider using another format instead of XML, but I'll need more investigation.
>> Sounds good!... May be, whe you get you 'next wersion with debugging feature, you may wish to have a double side 'Joomla! 2.5.7 installations, one were to install a 'tracktime' component and other where to install the plugin inside the same servers the others (I hope that could help you to see the problem closely)

Arrived the momment, just email me dorectly (you already have my emaill address) and I'll be very happy to build both temporal sites for your test.

I'll stay tuned to your next input / feedback,
Rgrds

Of course!
Both sites running inside the same servers where I suffered the reported issue. They will be ready by tomorrow evening as latest...
I will email you with your SU + FTP login credentials for each site.
Stay tuned,
Rgrds,